If you reject the concept of individual revelation then you reject Paul and reject the spiritual gifts. For how can an individual have a calling to a task without the individual revelation and gifting by the Holy Spirit? As to the authority beyond the bible, you are confused. The bible is the text and testament of the Word. In the beginning was the Word, and the Word was with God, and the Word was God. The bible needs no other authority as it comes from God.
The Nevi’im and Ketuvim were added because they contained the continuing revelations of God to the sinners as to how God will would make up for man’s failings and falling away. They lay the foundations for how Jesus would come and would make the ultimate sacrifice .... and fulfill the Torah.
Following that pattern, the Gospels, like the Torah, show the mercy of God by sending his Son. Can one live their life according to the Torah, yes. Can one live their life according to the Gospels, yes. However, just as the other books of the Tanakh help individuals to take comfort and strength from examples both good and bad, the Acts and Epistles help man relate to the message of God. They provide examples to guide the foundling and floundering Christian.
The Bible clearly lays out the authority of Christ as head of the Church. Not pope, pastor or priest or other worldly authority. The Bible does NOT lay out a structure for the Church. There are only gifts of the Holy Spirit that are to be used to fulfill the mission of the church. Those roles are:
Apostle
Prophet
Evangelist
Pastor
Teacher
To that Apostles added the roles of Deacon and Bishop. To the Deacon was given the role of the distribution of charity. To the Bishop was given the role of steward of the local Christians. The Bishop is not given the role of interceding on behalf of others. The Bishop is not given the role of inserting themselves between the flock and Christ. There are no rulers nor kings nor princes nor masters of Christians. There is no authority of one Bishop over another Bishop or Popes over Bishops. All first century churches were local churches serving and worshiping in their local communities.
What is clearly stated in the bible is that we as individuals are all responsible for our own walk. That we must approach our own salvation with fear and trembling because if we get it wrong, the price is terrible. On the day of judgement, no person will stand before God on our behalf ... unless, and only if we have a personal relationship with Jesus.
I am not denying individual, personal revelation and I never did. How do you judge a spiritual gift? By what authority?
See here for how the Ketuvim came to be: http://en.wikipedia.org/wiki/Ketuvim
The people added to them and they weren’t canonized until well after Jesus’ ascension and the deaths of the last Apostles.
How is one set apart to the calling of an Apostle or Prophet, an Evangelist, a Pastor or a Teacher? Who has the authority to do that? Which of the above are able to cast out devils/demons? Which can anoint the sick? How is that done?
You are responsible for your own “walk” with God. In the end, we are all saved individually or not, but there isn’t chaos in the Church, but order.